It would be extremely helpful, esp. for dot1x, for VM to have the ability to be mapped to a USB Device. While this might be possible with the qemu advanced commands, it would be helpful to have a GUI/dropdown to perform the mapping.

The big use case would be, having a Windows (or other OS) VM being able to directly connect to the USB Device, specifically like a USB NIC, that then can plug into a real network switch that can detect layer 1 / 2 changes which dot1x uses to kick off processes.

I understand how it can be done through a bridged connection, it just the added flexibility to have a host being able to be mapped to an external USB device (NIC), so you can initiate actual state of the interface. With a bridged connection the NAD (switch) always sees the host as up, and you would have to kick off a manual shut/no shut to kick off dot1x. Also, having external NIC for a host allows for connecting to the the real switch for TrustSec (not that you can't do it with a bridge connection). Just ease of use.